WASHINGTON - Who should get a preference when it comes to immigrants? For decades, relatives of those already in the United States have moved to the front of the line.

The White House and senior Republican lawmakers now want to strictly limit the influx of family members and give preference to skilled workers sought by employers. Democrats say that is inhumane and impractical.

Sen. Edward M. Kennedy, D-Mass., says the issue has become "one of the most contentious" in pulling together a broad immigration bill upon which Republicans and Democrats can agree. The idea is to give many of the nation's 12 million illegal immigrants a chance at citizenship and create a guest-worker program for new arrivals.

"It would be a huge mistake to expand employment-based immigration at the expense of our historic tradition of family-based immigration," Kennedy, one of the key negotiators, said this week.

Nearly two-thirds of legal permanent residents admitted last year were family- sponsored immigrants, while less than 12.6 percent came in based on employment preferences, according to the Homeland Security Department. Roughly one-fourth fell into other categories, such as refugees and asylum seekers.

Reshaping immigration laws is a priority for President Bush, who wants it as part of his domestic legacy. It also would be a popular achievement for Democrats to take to voters in the next election.

Senate Democratic leaders have promised to bring up a measure, with or without GOP agreement, within two weeks.

Bush put in a plug Wednesday for a swift compromise. "I will work with both Republicans and Democrats to get a bill to my desk before the summer is out, hopefully," he told a contractors' trade group in Washington.

Curbing the flow of immigrants' family members into the United States - sometimes referred to as "chain migration" - has become a cause celebre for Sen. Jon Kyl, R-Ariz., a prominent conservative trying to broker the deal.

The White House, working to win Republican support for an immigration overhaul, included Kyl's hard-line stance on family members in an early discussion draft and has sought to preserve at least some limits as part of any compromise.

Under the White House proposal, legal immigrants would lose the right to petition to bring adult children and siblings to the United States. They could do so for spouses and minor children, but their ability to sponsor parents would be severely limited.

The proposal would limit or end preferences for people who had family members living legally in the U.S., and award many more visas based on employability criteria, such as education and skills. Temporary workers could not bring family members at all unless they met a certain wealth threshold and had health insurance. Last year's Senate-passed immigration bill did not change the treatment of family members. Conservatives are pleased the issue is now on the table; Democrats are alarmed. A spat among Senate aides over how to draft the family-related provisions led to a blowup last week, briefly stalling the negotiations. The talks picked up again this week. Sen. John Cornyn, R-Texas, said the vast majority of legal immigrants have entered the country on the basis of a family-based preference, meaning they "have no bearing on our national competitiveness or our global race for brains." Changing that, he said, is "a central reform." Religious groups and Asian-American advocacy organizations are among the strongest opponents of the proposed changes. "It would be a historic shift in U.S. immigration policy for them to do this," said Kevin Appleby of the U.S. Conference of Catholic Bishops. "Immigration reform cannot be won on the backs of families. ... You can't do reform on the cheap that way." Karen Narasaki of the Asian American Justice Center said the proposal to do away with family-based visa preferences is "a cold calculation about numbers. They're trading off families for employers." "They forget that there's value in family, that family is necessary in order to help immigrants integrate," Narasaki said. Anti-immigration activists, however, say numbers matter. "Our view is that the numbers are too high and we have to look at where they should be cut, and these (family) categories, it seems to us, are the easiest to cut because there's no real justification for them," said Rosemary Jenks of NumbersUSA. Matthew Spalding, an analyst at the conservative Heritage Foundation, said allowing guest workers to bring family members puts a burden on taxpayers and encourages temporary workers to settle permanently in the U.S. "Having (family preferences) defined too broadly essentially causes one to lose control of one's immigration policy," Spalding said. "To cut some sort of deal, they've got to figure out ways to keep this all under control." Recent polls have shown that people overwhelmingly support giving illegal immigrants a path to citizenship, creating a temporary worker program and strengthening border security. But voters are more ambivalent about family-based immigration. "People are really supportive of family immigration as a principle," said pollster David Mermin. "At the same time, there's this feeling that there need to be some limits, and nervousness about how easy and how extensive it will be." AP-CS-05-02-07 1439EDT